A winner take all (WTA) circuit is called by various names such as a winner-take-all circuit, a maximum/minimum value extractor, a maximum/minimum level circuit, and a position determining circuit and is widely used in a various industrial fields such as a multi-channel optical array detector application technology and a logic circuit neural network system.
Circuits developed until now provide only the positions and amplitude of channels having a maximum/minimum voltage value or current value input during a predetermined time by using only a switching function of a transistor. In other words, a capability of determining an accurate time at which a response is generated is not provided. In addition, according to conventional technologies, it is difficult to simultaneously correct an offset error occurring due to a level difference between input voltages and a response position output error and count losses in a situation in which a plurality of input signals having the same magnitude are generated.
Furthermore, a conventional position determining algorithm uses a method in which maximum/minimum of voltage values are divided. However, in an industrial field in which a light source having a specific magnitude is to be detected in a situation in which various light sources are present, it is difficult to use the above-described prior arts. For example, in an industrial field of a light source analysis or the like in which the degree of the occurrence frequency of a light source having a magnitude of 200 mV and a probability distribution of response positions thereof are analyzed in a situation in which various light sources having energy levels of 100, 200, 300, and 400 mV are present, an algorithm capable of detecting only a specific signal level is required.
In addition, in an industrial field in which the position of a response input first is to be acquired from among input signals having a predetermined or higher voltage level, it is difficult to use the above-described prior arts. For example, an algorithm is necessary which can be applied to a situation in which a signal according to a fastest response is to be extracted from among a plurality of input signals in a case where a coincidence event is measured using two detectors as in the case of a PET imaging equipment.